The invention pertains to a backrest having two vertical, laterally undivided stationary supportive areas and a central supportive area therebetween and including height adjustable guide headrest.
In the case of a known backrest of this type as described, for example, in DE 92 06 122 U1, lateral supportive areas, which assure the requisite lateral support for the user, adjoin a central backrest area. Between the lateral supportive areas, at the upper end of the central area, a headrest is provided in such a manner that its height may be adjusted.
Such a backrest allows nothing more than the adjustment of the headrest to the varying size of various users of the seat. The portion of the backrest that continually accepts and supports the user""s back, is not variable in the case of such designs, and accordingly, it can be anatomically correct only for those seat users who fall within a certain size range.
Taking this state of the art as a point of departure, it is a purpose of the present invention to embody a backrest of the known type in such a way that it is adjustable in the central region lying beneath the headrest in such a manner that persons of varying sizes are well supported.
This task is accomplished with the backrest of the present invention characterized in that the central supportive area, which is provided beneath the headrest, is embodied so as to be divided horizontally into a lower and a central section, wherein the lower section is embodied so as to be stationary, and the central section is embodied in such a way that it may be repositioned with respect to height.
As a result of the possibility of separate adjustment of an upper area of the backrest, which encompasses the headrest, and a central zone of support, the supporting effect, and thus, the comfort, of seat users of varying sizes is improved. Such a backrest can be simply adapted to various upper body dimensions. This adaptation permits one to sit free of fatigue, even over longer distances of travel.
In the case of a particularly preferred embodiment form, the gaps of demarcation between adjacent sections of the backrest are bridged by finger-shaped projections that engage with one another, so that the supporting effect, which is transferred upwardly, can be manifested uniformly across the entire height of the upper body.
As height increases, the distance of the head from the surface of the seat increases by approximately twice the amount of the distance of the shoulder area. Therefore, according to the invention, in the case of an additional preferred embodiment, the path of the upper section""s progress is, in each case, twice as great as that of the central section.